The present invention relates to a drive apparatus for moving an object at a speed which is a predetermined function of time. The movement of the object may be rotary or reciprocating (linear or rotary).
Such drive systems have been developed which control speed in accordance with a phase difference between periodic command and actual speed signals. The control is very accurate since it is independent of the position of the object. A typical system of this type is disclosed in Japanese application No. 53-101852.
The problem which has heretofore remained unsolved is that the system has required expensive and complicated circuitry including adders, subtractors, comparators, discriminators, switches, etc. Another problem is the large number of circuit elements which require periodic fine adjustment.